ContextHubService: Hack around 32-bit app ID

The NanoApp.java class has a bug (b/30808791) where the API treats
app IDs as 32-bits, instead of 64-bits.  We are too late in the
Android N release cycle to change this API.

We previously put in a hack to fix this only for Google nanoapps.
However, our GTS nanoapps need this to work, and there are other
partners who need this to work in the N timeframe.  So we make
a more robust hack which parses the full 64-bit app ID out of
the header binary.

Test: Compiles and runs GTS
Bug: 31767599
Change-Id: Ic43f1f62c685fb99aac08d08767d1a67c329503f